July 19, 2009

This week, a short episode featuring a heap of positive feedback on the Integrate ’09 vendors episode.
Then, Bomar asked if he should buy an audio interface with some DSP that he can track through, or should he just record clean and use plugins later,
and David McKeitch brought us up to speed on his indie-film tracking project.

Oh, and a reminder that there’ll be no podcasts at all next week, as Cath, Max and I are away on holiday.

In the last 2 weeks, I’ve recorded several interviews at 2 different trade shows. Those interviews have ended up in episodes of both Shutters Inc and Sine Lanugage.
In the wake of this, I’ve had a couple of enquiries from listeners as to my technique for recording interviews on flash-based field recorders like the Zoom H2.
These listeners have commented that they never seem to achieve the same level of results as I have managed, and have asked for some insights.
So, I shall endeavour to outline the pitfalls as I understand them.

First off, tempting though it may be, do not record to mp3!
Remember, mp3 is a lossy format, and we don’t ever want to save production audio (clips which still need further work before release) in a lossy format.
And for that matter, don’t record at 16 bit wav either.
No, your preferred option is to record 24 bit wav.
Yes, it will chew up your memory cards quicker, but memory cards are really not that expensive these days, so carrying a couple of extras shouldn’t represent too much of a burden, either physically or financially.
If your recorder of choice does not offer 24 bit wav, then fall back to recording 16 bit wav instead.

Secondly, your recorder SHOULD offer a choice of microphone gain sensitivities.
The Zoom H2 offers low, medium and high.
Low will turn the sensitivity down (useful for really loud sources), medium is what it sounds like, and high turns the sensitivity up (for really quiet sound sources).
I have found that the medium setting usually works well for these trade show interviews, but obviously, judge each on a case by case basis.
Remember, we are recording at 24 bit, so we don’t NEED to peg the meters at zero!
Peaks of -20dB to -12dB are just fine!

Third, if your recorder of choice has a headphone output (I don’t imagine there’d be any which do not, but you never know), then absolutely have some form of monitoring with you when you are recording.
This may be a set of lightweight street headphones, or even a decent set of earbuds.
Me? I use my trusty old Sennheiser CX300’s, with just one earbud stuck in one ear.
The reason for that is that through that ear, I can hear what the microphone is picking up, and through my other ear, I’m hearing the world around me.

Now, because you are monitoring (via your earbud) what the microphone of the recorder is hearing, you are able to move the recorder around as necessary througout the interview to make sure the talent stays ‘on mic’.
Now, you might be thinking that people aren’t going to like having a flash recorder stuck in (and moving around in front of) their face.
I would contend that if they have agreed to do an interview, then they are probably going to be ok with it.
My technique is to hold the recorder at chest height between myself and the talent.
That way, you SHOULDN’T get any plosives (pops), but the mic should be able to hear the talent fairly well, while keeping the ambient noise reasonably under control.
If you talent is a very soft speaker, then you may have to move the recorder closer toward them, and that may feel a little uncomfortable at first.
If the talent keeps backing away from the mic, stop the interview, explain to them that you NEED the mic that close in order to hear what they are saying without being drowned by background noise, then recommence the interview.
Thing is, MOST of the time, the person you’ll be interviewing is from the marketing department or the sales team and they generally don’t speak that quietly!!

OK, so now you’re back at your desktop (or in your hotel room working on your laptop) and ready to edit and mix.
Drag the files into your DAW of choice.
DO NOT go and normalise the waveforms!
Remember, they’re 24 bit files, so it’s all good.
In your multitrack (which is also mixing at 24 bits or higher, right? RIGHT??), lay up your interviews where you want them.
Adjust the gain so you’ve got peaks around -20dBFS to -15dBFS off each channel. At this point, you should have NO processing on your master output.
Put in some per channel automation to keep each interview roughly in the bacllpark in terms of output level. You don’t have to get too finicky with it, just ‘in the ballpark’ will be good enough at this stage.
Now, if your final audio piece is going to feature other pieces of audio as well, I’d suggest setting up a submix (buss) for just the interviews to go through.
Then, slap a peak limiter across that buss with an output level set for -15dBFS, and the threshold set so that you’re getting about 4-6dB of gain reduction on that peak limiter.
Then, AFTER the peak limiter, put a compressor with a moderate attack (~20-30ms), moderate release (~100-150ms), a medium ratio (3:1-5:1) and again, enough threshold to give you another 3-6dB of gain reduction.
Your interview submix should now be exhibiting tightly controlled dynmaics, but not sounding squashed.
Go ahead and mix it in with all your other audio bits so that everything sounds roughly equal in apparent volume.
Slap a peak limiter across your master output, and you should be cookin’ with gas!
Have fun!

In episode 107, Rob Scalise gets on my soapbox about the potential dangers of prolonged use of headphones.
My man in Hollywood got back to us with answers to Jay’s questions from ep 106 re: movie audio.
Ernie wrote and mentioned that he prefers my AKG C3000 to my R84. He also commented on previous assertions that my podcasts were distorted, and asked about recording nature sounds with field recorders and what would be the best way to approach it.
This led me off on a discussion of how it’s not JUST the microphone which influences our perception of the recorded sound, but that the mic preamp, plus any outboard gear etc etc also play a big role.
Which then led me off an a train of thought related to Slau’s latest podcast episode where he did a shootout between a whole bunch of large diaphragm condensor mics.

This week, a ton of e-mail to answer from the last month or so,
including some reminiscing about the transition from analogue to digital within the radio industry through the late ’80’s and early ’90’s,
Ron Eastwood tried recording quasi-binaural on a boom box,
Jim Addie sent in a link to an interesting article on the merits, or lack thereof, of recording at higher sample rates and longer wordlengths (when I recorded this episode, I commented that I hadn’t read the entire article. I now have, and have the feeling that at some point in the past, I’ve been pointed to it, and have actually read it. Still, it was good to read it again!),
Greg Andreson (who is all “Bruced” out) wrote to tell me about his Zooms (the H2 and the H4!) and how much he likes them, and to comment on the wildly different standards of audio production that exist within the podcaster community,
and Pascal asked about sidechain compression.
One free VST plugin that I know of which does sidechain compression is Sidekick.
And finally, a bit of a chat about what is in store for episode 100.

August 31, 2008

This week, a bunch of listener e-mails to answer.
First up, we heard from Bomar in France. After editing and mixing this episode, it occurred to me that this really should have been in Sine Language rather than BTP… oh well, sue me!
Bomar mentioned (among other things), a microphone which is alledgedly capable of picking up the sound of an ant’s footsteps.
Unfortunately, the site doesn’t appear to have any audio samples of this awesome feat.
Mmmmmm, sorry Bomar, but please forgive my scepticism!
Bomar went on to talk about field recorders, which led to a discussion on ‘auto gain control’ circuits (and why I don’t like them).

Next up, I received an e-mail from Ken at Bear Creek Studios who alerted me to a piece of software called Mediasweeper.
This looks really nifty, although I do need to spend some more time with it.
What it is designed to do is to look at your Audition .ses files and show you a list of which assets (read: wav files, mp3’s, avi’s, whatever) are referenced by the session file, and then allow you to either move all those files, or delete any wavs in the project folder which are NOT referenced by the session file!
If it does as promised, this will be a God-send!
Unfortunately, there’s no help file with it.
When I’ve spent some more time with it, I’ll report back.

Then, Wayne Montle wrote to tell me about Pamela, a piece of software which sits in between Skype and your DAW of choice.
What it does is allow you to split your outgoing audio (your voice) and your incoming audio (the person you’re talking to) into a left/right stereo signal so that you can later edit your Skype call with split tracks.
For those with soundcards which don’t offer that flexibility natively, this could be a huge blessing.
Thanks for the tip, Wayne.

Finally, I received an e-mail from Patrique Osborne who was concerned that I was advocating the growing of marijuana in episode 124!
I had a good laugh at this.

This week, so many e-mails to answer, I couldn’t get to them all!Jim Addie chimed in with some follow up on DC offset (thanks, Jim!),
Steve Mayfield wondered if I’d got my HDMI issues sorted (Yes! Thanks, Steve).
He offered a link to another site that reviewed some hand held field recorders, registered his ‘vote of confidence’ for a video podcast for SL100, and expressed his appreciation of the new audio2u.com podcast imaging.
Then, we heard from Ike Tamigian who owns the Tascam 122L audio interface and reckons that “for the money you can’t go wrong”. Thanks Ike!
Then, Noel Payne asked about what eq filters (high pass, low pass, notch, band pass etc) to use under what circumstances. And after I finished editing the podcast, I realised there’s more I need to add to this topic, next week. Stay tuned, Noel!
And finally, Ron Eastwood wrote in with a photography analogy regarding sample rate and bit resolution, and asked what is the most important factor (with regards audio quality)?

March 9, 2008

This week,
Scott Hess discovered why it’s a good idea to disable Windows sound events,
Bruce is heading back to the States for NAB (Yay!!!!),
the Marantz PMD 620 arrived for me to play with,
I need your help on a couple of things,
and Bruce is now on Facebook.